scholarly journals LiDAR-Based Regional Inventory of Tall Trees—Wellington, New Zealand

Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 702 ◽  
Author(s):  
Jan Zörner ◽  
John Dymond ◽  
James Shepherd ◽  
Susan Wiser ◽  
Ben Jolly
Keyword(s):  
New Zealand ◽  
High Performance ◽  
Tree Height ◽  
Airborne Lidar ◽  
Aerial Photographs ◽  
Fast Method ◽  
Height Distribution ◽  
Detection Scheme ◽  
Crown Delineation ◽  
Indigenous Forest

Indigenous forests cover 23.9% of New Zealand’s land area and provide highly valued ecosystem services, including climate regulation, habitat for native biota, regulation of soil erosion and recreation. Despite their importance, information on the number of tall trees and the tree height distribution across different forest classes is scarce. We present the first region-wide spatial inventory of tall trees (>30 m) based on airborne LiDAR (Light Detection and Ranging) measurements in New Zealand—covering the Greater Wellington region. This region has 159,000 ha of indigenous forest, primarily on steep mountainous land. We implement a high-performance tree mapping algorithm that uses local maxima in a canopy height model (CHM) as initial tree locations and accurately identifies the tree top positions by combining a raster-based tree crown delineation approach with information from the digital surface and terrain models. Our algorithm includes a check and correction for over-estimated heights of trees on very steep terrain such as on cliff edges. The number of tall trees (>30 m) occurring in indigenous forest in the Wellington Region is estimated to be 286,041 (±1%) and the number of giant trees (>40 m tall) is estimated to be 7340 (±1%). Stereo-analysis of aerial photographs was used to determine the accuracy of the automated tree mapping. The giant trees are mainly in the beech-broadleaved-podocarp and broadleaved-podocarp forests, with density being 0.04 and 0.12 (trees per hectare) respectively. The inventory of tall trees in the Wellington Region established here improves the characterization of indigenous forests for management and provides a useful baseline for long-term monitoring of forest conditions. Our tree top detection scheme provides a simple and fast method to accurately map overstory trees in flat as well as mountainous areas and can be directly applied to improve existing and build new tree inventories in regions where LiDAR data is available.

scholarly journals Estimation of diameter and height of individual trees for Pinus sylvestris L. based on the individualising of crowns using airborne LiDAR and the National Forestry Inventory data.

2016 ◽  
Vol 25 (1) ◽  
pp. 046 ◽  
Author(s):  
Manuel-Ángel Valbuena-Rabadán ◽  
Jacinto Santamaría-Peña ◽  
Félix Sanz-Adán
Keyword(s):  
Pinus Sylvestris ◽  
Tree Height ◽  
Point Clouds ◽  
National Forest Inventory ◽  
Airborne Lidar ◽  
National Forest ◽  
Autonomous Community ◽  
Total Height ◽  
Crown Delineation ◽  
Geometrical Relationships

Aim of study: The objective of this study is to test the validity of the DBH and total height allometric models fitted to the crown polygon data obtained by the application of a crown delineation and individualisation algorithm which uses the geometrical relationships between the points in the original LiDAR point clouds in the Pinus sylvestris L. stands.Area of study: The study area is located in the province of Álava in the Autonomous Community of the Basque Country.Material and Methods: The crowns are delineated using data from airborne LiDAR point clouds obtained in the 2008 overflight of the Basque Autonomous Community. The DBH and total height data for field trees are obtained from the plots in the 4th National forest inventory.Main Results: For the adjusted total height and DBH models coefficients of determination of 0.87 and 0.74 respectively were obtained. The root mean squared errors were 10.67% and 18.97% respectively. The distributions of obtained DBH and total height fitted values and the distributions of the DBH and total height of the field trees are very similar except for the DBH below 15 cm.Research highlights: For stands of Pinus sylvestris L. in Álava, the geometrical relationships between the points that correspond to laser signal echoes obtained with airborne LiDAR sensors can be used directly to delineate approximations of the horizontal projections of the crowns of the trees. Although the procedure set out here was developed for stands of P. sylvestris L. in Álava, it can be applied to other conifers in regular stands by adjusting the working parameters of the function which delineates the crowns on the basis of the point cloud.Abbreviations used: IFN4: 4th National Forest Inventory; Ht: Field Tree Height; Hl: LiDAR Tree Height; DCL: LiDAR Crown Diameter.

scholarly journals Mapping Physiognomic Types of Indigenous Forest in New Zealand Using Space-Borne SAR, Optical Imagery and Air-Borne LiDAR

2019 ◽  
Author(s):  
John R. Dymond ◽  
Jan Zörner ◽  
James D. Shepherd ◽  
Susan K. Wiser ◽  
David Pairman ◽  
...  
Keyword(s):  
New Zealand ◽  
Classification Accuracy ◽  
Structural Information ◽  
Remote Sensing Data ◽  
Airborne Lidar ◽  
Canopy Height ◽  
Support Vector ◽  
Alos Palsar ◽  
Optical Imagery ◽  
Indigenous Forest

Indigenous forests cover 24% of New Zealand and provide valuable ecosystem services. However, a national map of forest types, that is, physiognomic types, which would benefit conservation management, does not currently exist at an appropriate level of detail. While traditional forest classification approaches from remote sensing data are based on spectral information alone, the joint use of space-based optical imagery and structural information from synthetic aperture radar (SAR) and canopy metrics from air-borne Light Detection and Ranging (LiDAR) facilitates more detailed and accurate classifications of forest structure. We present a support vector machine (SVM) classification using data from ESA’s Sentinel-1 and 2 missions, ALOS PALSAR, and airborne LiDAR to produce a regional map of physiognomic types of indigenous forest in New Zealand. A five-fold cross-validation of ground data showed that the highest classification accuracy of 80.9% is achieved for bands 2, 3, 4, 5, 8, 11, and 12 from Sentinel-2, the ratio of bands VH and VV from Sentinel-1, HH from PALSAR, and mean canopy height and 97th percentile canopy height from LiDAR. The classification based on the optical bands alone was 73.1% accurate and the addition of structural metrics from SAR and LiDAR increased accuracy by 7.8%. The classification accuracy is sufficient for many management applications for indigenous forest in New Zealand, including biodiversity management, carbon inventory, pest control, ungulate management, and disease management. National application of the method will be possible in several years, once national LiDAR coverage is achieved, and a national canopy height model is available.

scholarly journals Species-specific basic stem-wood densities for twelve indigenous forest and shrubland species of known age, New Zealand

2021 ◽  
Vol 51 ◽  
Author(s):  
Michael Marden ◽  
Suzanne Lambie ◽  
Larry Burrows
Keyword(s):  
New Zealand ◽  
Wood Density ◽  
Tree Height ◽  
Stem Wood ◽  
Breast Height ◽  
Increased Temperature ◽  
Density Values ◽  
Indigenous Forest ◽  
Species Specific ◽  
Softwood Species

Background: Tree carbon estimates for New Zealand indigenous tree and shrub species are largely based on mean basic stem-wood densities derived from a limited number of trees, often of unspecified age and from a limited number of sites throughout New Zealand. Yet stem-wood density values feed directly into New Zealand’s international and national greenhouse gas accounting. We augment existing published basic stem-wood density data with new age-specific values for 12 indigenous forest and shrubland species, including rarely obtained values for trees <6-years old, across 21 widely-distributed sites between latitudes 35° and 46° S, and explore relationships commonly used to estimate carbon stocks. Methods: The volume of 478 whole stem-wood discs collected at breast height (BH) was determined by water displacement, oven dried, and weighed. Regression analyses were used to determine possible relationships between basic stem-wood density, and tree height, root collar diameter (RCD), and diameter at breast height (DBH). Unbalanced ANOVA was used to determine inter-species differences in basic stem-wood density in 5-yearly age groups (i.e. 0–5 years, 6–10 years etc.) (P<0.05). As specific taxa of Kunzea ericoides (Myrtaceae) has only been identified at some study sites we combine the data from each site, and use the term Kunzea spp. We compare our age- and species-specific results with existing published data where age is specified versus non-age-specific values. Results: Kunzea spp. and Leptospermum scoparium exhibited positive correlations between basic stem-wood density and tree height, RCD, and DBH. No relationships were established for Melicytus ramiflorus, Coprosma grandiflora, Weinmannia racemosa ?6-years old, or for Podocarpus totara, Agathis australis, Vitex lucens, and Alectryon excelsus <6-years old. Dacrydium cupressinum and Prumnopitys ferruginea <6-years old exhibited a significant positive relationship with DBH only, while for Dacrycarpus dacrydioides, each correlation was negative. Irrespective of age, basic stem-wood density is not different between the hardwood species L. scoparium and Kunzea spp. but is significantly greater (P=0.001) than that of the remaining, and predominantly softwood species of equivalent age. For Kunzea spp., L. scoparium, Coprosma grandiflora, Weinmannia racemosa, and Melicytus ramiflorus ?6-years old there was no evidence that basic stem-wood density increased with tree age, and values were within the range of published and unpublished data. For naturally reverting stands of Kunzea spp. located between latitudes 35° to 46° S, basic stem-wood density values tended to increase with decreased elevation and increased temperature. Conclusions: Increasing basic wood density values in Kunzea spp. with decreased elevation and increased temperature suggest that where local data are available its use would improve the accuracy of biomass estimates both locally and nationally. Furthermore, refining biomass estimates for existing communities of mixed softwood species, stands of regenerating shrubland, and new plantings of indigenous species will require additional basic stem-wood density values for scaling from stem wood volume to total stand biomass.

scholarly journals Cloth simulation-based construction of pit-free canopy height models from airborne LiDAR data

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Wuming Zhang ◽  
Shangshu Cai ◽  
Xinlian Liang ◽  
Jie Shao ◽  
Ronghai Hu ◽  
...  
Keyword(s):  
Tree Height ◽  
Point Clouds ◽  
Airborne Lidar ◽  
Canopy Height ◽  
Lidar Data ◽  
Cloth Simulation ◽  
Simulation Based ◽  
Maximum Tree Height ◽  
Airborne Lidar Data ◽  
Better Than

Abstract Background The universal occurrence of randomly distributed dark holes (i.e., data pits appearing within the tree crown) in LiDAR-derived canopy height models (CHMs) negatively affects the accuracy of extracted forest inventory parameters. Methods We develop an algorithm based on cloth simulation for constructing a pit-free CHM. Results The proposed algorithm effectively fills data pits of various sizes whilst preserving canopy details. Our pit-free CHMs derived from point clouds at different proportions of data pits are remarkably better than those constructed using other algorithms, as evidenced by the lowest average root mean square error (0.4981 m) between the reference CHMs and the constructed pit-free CHMs. Moreover, our pit-free CHMs show the best performance overall in terms of maximum tree height estimation (average bias = 0.9674 m). Conclusion The proposed algorithm can be adopted when working with different quality LiDAR data and shows high potential in forestry applications.

scholarly journals Comparative Profiling and Discovery of Novel Glycosylated Mycosporine-Like Amino Acids in Two Strains of the Cyanobacterium Scytonema cf. crispum

2016 ◽  
Vol 82 (19) ◽  
pp. 5951-5959 ◽  
Author(s):  
Paul M. D'Agostino ◽  
Vivek S. Javalkote ◽  
Rabia Mazmouz ◽  
Russell Pickford ◽  
Pravin R. Puranik ◽  
...  
Keyword(s):  
Amino Acids ◽  
New Zealand ◽  
Uv Radiation ◽  
High Performance ◽  
Parent Compound ◽  
Future Research ◽  
Content Type ◽  
Chromatography Analysis ◽  
Paralytic Shellfish Toxins ◽  
Cell Extracts

ABSTRACTThe mycosporine-like amino acids (MAAs) are a group of small molecules with a diverse ecological distribution among microorganisms. MAAs have a range of physiological functions, including protection against UV radiation, making them important from a biotechnological perspective. In the present study, we identified a putative MAA (mys) gene cluster in two New Zealand isolates ofScytonemacf.crispum(UCFS10 and UCFS15). Homology to “Anabaena-type”mysclusters suggested that this cluster was likely to be involved in shinorine biosynthesis. Surprisingly, high-performance liquid chromatography analysis ofS. cf.crispumcell extracts revealed a complex MAA profile, including shinorine, palythine-serine, and their hexose-bound variants. It was hypothesized that a short-chain dehydrogenase (UCFS15_00405) encoded by a gene adjacent to theS. cf.crispummyscluster was responsible for the conversion of shinorine to palythine-serine. Heterologous expression of MysABCE and UCFS15_00405 inEscherichia coliresulted in the exclusive production of the parent compound shinorine. Taken together, these results suggest that shinorine biosynthesis inS. cf.crispumproceeds via anAnabaena-type mechanism and that the genes responsible for the production of other MAA analogues, including palythine-serine and glycosylated analogues, may be located elsewhere in the genome.IMPORTANCERecently, New Zealand isolates ofS. cf.crispumwere linked to the production of paralytic shellfish toxins for the first time, but no other natural products from this species have been reported. Thus, the species was screened for important natural product biosynthesis. The mycosporine-like amino acids (MAAs) are among the strongest absorbers of UV radiation produced in nature. The identification of novel MAAs is important from a biotechnology perspective, as these molecules are able to be utilized as sunscreens. This study has identified two novel MAAs that have provided several new avenues of future research related to MAA genetics and biosynthesis. Further, we have revealed that the genetic basis of MAA biosynthesis may not be clustered on the genome. The identification of the genes responsible for MAA biosynthesis is vital for future genetic engineering.

A comment on scaling methane emissions from vegetation and grazing ruminants in New Zealand

2006 ◽  
Vol 33 (7) ◽  
pp. 613 ◽  
Author(s):  
Francis M. Kelliher ◽  
Harry Clark ◽  
Zheng Li ◽  
Paul C. D. Newton ◽  
Anthony J. Parsons ◽  
...  
Keyword(s):  
New Zealand ◽  
Standard Deviation ◽  
Forest Canopy ◽  
Emission Rate ◽  
Oxidative Capacity ◽  
Emission Rates ◽  
Ch4 Emission ◽  
Ch4 Emissions ◽  
Grazed Pasture ◽  
Indigenous Forest

Keppler et al. (2006, Nature 439, 187–191) showed that plants produce methane (CH4) in aerobic environments, leading Lowe (2006, Nature 439, 148–149) to postulate that in countries such as New Zealand, where grazed pastures have replaced forests, the forests could have produced as much CH4 as the ruminants currently grazing these areas. Estimating CH4 emissions from up to 85 million ruminants in New Zealand is challenging and, for completeness, the capacity of forest and pastoral soils to oxidise CH4 should be included. On average, the CH4 emission rate of grazing ruminants is estimated to be 9.6 ± 2.6 g m–2 year–1 (±standard deviation), six times the corresponding estimate for an indigenous forest canopy (1.6 ± 1.1 g m–2 year–1). The forest’s soil is estimated to oxidise 0.9 ± 0.2 g m–2 year–1 more CH4 than representative soils beneath grazed pasture. Taking into account plant and animal sources and the soil’s oxidative capacity, the net CH4 emission rates of forest and grazed ecosystems are 0.6 ± 1.1 and 9.8 ± 2.6 g m–2 year–1, respectively.

scholarly journals Protein supplements between consumer's opinion and quality control: an applied study in jordan

2019 ◽  
Vol 10 (3) ◽  
pp. 1961-1969
Author(s):  
Talal Aburjai ◽  
Rudaina Othman Yousif ◽  
Mahmood Jasim AlSamydai ◽  
Ali Al-Samydai ◽  
Farah Al-Mamoori ◽  
...  
Keyword(s):  
High Performance ◽  
Chromatographic Method ◽  
The Other ◽  
Primary Study ◽  
Fast Method ◽  
Reverse Phase ◽  
Protein Supplements ◽  
Sports Clubs ◽  
Applied Study ◽  
Other Substances

The consumption of dietary supplements has nowadays become popular, especially in Jordanian sports clubs and gyms. In fact, there is a widespread idea, among consumers, that these proteins contain hormones in order to increase their efficiency. The objective of this study is to develop a better understanding of customer opinion in an era that increased growth in Jordan and improves a chromatographic method to detect the testosterone in protein supplements. The method of this study, six popular types of proteins in the Jordan market have been chosen after conducting a primary study of the proteins' users by questionnaires to identify their opinions about these proteins. These proteins have been analyzed by reverse-phase high-performance liquid chromatography by developing an easy and fast method to detect testosterone signal between 8-9 minutes of the chromatogram. The results of the study showed that 61% of the users believe that sport proteins contain hormones and other substances that are not mentioned in the list of ingredients. While 39% believe otherwise. On the other side, HPLC results of six proteins showed no signs for testosterone hormone. The main reason that drives them to take sport proteins is for building muscles in spite of they believe it could be harmful due to containing hormones and other substances. So in future investigations, it might be possible to use different brands and investigate them by using the same method.

scholarly journals Estimation of Tree Height and Forest Biomass Using Airborne LiDAR Data: A Case Study of Londiani Forest Block in the Mau Complex, Kenya

2017 ◽  
Vol 07 (02) ◽  
pp. 255-269 ◽  
Author(s):  
Faith Kagwiria Mutwiri ◽  
Patroba Achola Odera ◽  
Mwangi James Kinyanjui
Keyword(s):  
Forest Biomass ◽  
Tree Height ◽  
Airborne Lidar ◽  
Lidar Data ◽  
Airborne Lidar Data

New Zealand study shows both gender and national culture influence impact of high-performance work systems (HPWS)

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Keyword(s):  
New Zealand ◽  
Job Performance ◽  
National Culture ◽  
Attribution Theory ◽  
High Performance ◽  
Service Sector ◽  
External Factors ◽  
Content Type ◽  
Mediating Role ◽  
The Impact

Purpose The authors based their study on the findings of attribution theory, which suggests some people attribute experiences at work to external factors, and others to internal factors. Their theory was that women and men made different attributions and this affected the impact of HPWS. Design/methodology/approach The authors sent out a questionnaire that tested whether ability was the main factor for male performance. And it tested if the main predictor of job performance for female employees was opportunity. The authors also considered the influence of national culture. The authors collected data from a purposive sample of service sector organizations in New Zealand. Findings All four of their hypotheses were supported showing that ability was the main predictor for males and external factors were the main predictor for women. In addition, the study found a mediating role existed for ability for males and opportunity for females in the HPWS-job performance relationship. Originality/value The authors said the main contribution of the research was to show the relevance of context in studies of employees. They said the research could contribute to understanding why motivation, as an AMO element, does not feature much in studies. In addition, highlighting the role of national culture helped to explain the formation of gendered behaviour. The authors felt it was reasonable to speculate that the results were impacted by New Zealand’s national culture.

Sign in / Sign up

Export Citation Format

Share Document